The present invention relates to a process or separating sugars from juices. Ultra filtration, nanofiltration and reverse osmosis (RO) membranes are employed to form a nutritious high sugar juice fraction and a low sugar juice fraction that is a low-calorie beverage. The low sugar juice fraction can be sweetend with a high potency sweetener such as aspartame.
U.S. Pat. No. 4,643,902 discloses a process where juices are passed through an UF membrane (30,000-100,000 daltons) to collect high molecular weight enzymes and spoilage microorganisms in the retentate and pass flavor and aroma components into the permeate. The retentate is treated to deactivate the enzymes and kill the microorganisms. The so treated retentate is then recombined to form a good tasting storage stable juice.
U.S. Pat. No. 4,322,448 discloses a method for concentrating fruit juices by reverse osmosis. The juice is passed through a first RO cellulose acetate membrane. The permeate is then passed through a second polymeric membrane which is non-polar relative to the first membrane. The retentate portions from each RO step are collected to form a concentrated fruit juice.
U.S. Pat. No. 4,933,197 discloses a membrane process for producing a fruit juice with improved quality where fruit juice is passed through a series of UF membranes of decreasing pore size. The first membrane removes spoilage microorganisms. The claimed product is a storage stable clarified juice serum which is the combination of all of the UF permeates.
U.S. Pat. No. 4,806,366 discloses a process for adjusting the alcohol content of alcoholic beverages employing RO techniques. Permeates are recirculated in that process.
WO 89/10703 of Bucher-Guyer relates to a process for the selective removal of sugar from beverages. A membrane separation is conducted to concentrate undesired compounds (sugars, acid) either in the permeate or retentate. The undesired compounds are then removed from the permeate or retentate by physical, chemical or biotechnological methods. RO techniques are employed to concentrate the undesired compounds.
Kimball et al, J. Agric Food Chem., Vol. 38, No. 6, 1990, disclose polymeric adsorbents for debittering California navel orange juice.
Matthews, et al., Food Technology, April, 1990, p. 130-132, disclose the removal of limonin and naringin from citrus juice by styrene-divinylbenzene resins.
Merson et al., Food Technology, Vol. 22, p. 631-634, disclose a juice concentration process using a reverse osmosis membrane filter.
Koseoglu et al, Food Technology, December, 1990, disclose the use of membrane technology to control enzymatic and microboal activity in juice processing as an alternative to traditional processing techniques. UF and reverse osmosis techniques are used to clarify, concentrate and sterilize juices.
Shomer et al, J. Food Science, Vol. 49, (1984) disclose UF processes for recovering citrus cloud from aqueous peel extract.